The penalty tax incurred for premature distributions from an IRA is:

Comprehensive and Detailed Step by Step Explanation:Premature distributions from an IRA (withdrawals before age 59½) are subject to a10% penalty tax (B)unless certain exceptions apply (e.g., disability, qualified education expenses, or first-time homebuyer withdrawals).

5% (A):Does not apply to IRS penalties.

10% (B):Correct. This is the standard penalty for early withdrawals.

20% (C):Represents mandatory withholding for certain distributions, not the penalty.

50% (D):Applies only to Required Minimum Distribution (RMD) failures, not premature distributions.

References:IRS Publication 590-B, Maryland IRA Penalty Exceptions Guidelines, COMAR 31.09.11.